Clean Air: Find Out How an Air Cleaner Can Improve Your Environment

Below is information that customers have found very helpful when making decisions on which air cleaner to choose. If you have a question that is not answered, please feel free to ask us and we will get back to you.

What Is The Air Quality Advantage Cell Difference?

PEL stands for permissible exposure limits enforced by the U.S. Occupational Safety and Health Administration, to protect workers against health effects linked to exposure to hazardous substances. PELs can be regulatory limits on the amount of a substance in the air or a concentration limit of a substance in the air and are based on 8-hour time weighted average (TWA) exposure. Learn more about PELs on OSHA.gov.

Threshold Limit Values (TLV®s) and Biological Exposure Indices (BEI®s) were developed as guidelines to assist in the control of health hazards in the practice of industrial hygiene. Visit the American Conference of Governmental Industrial Hygienists website for additional information.

What is a dust collector?

Dust collectors generally refer to industrial cleaners used in high contaminant loading applications. They commonly use compressed air to backflush the cartridges free of excessive contaminant to allow air to continue flowing. Commonly used in the collection of dust, smoke or any other dry contaminant. Not typically feasible for use with wet applications.

Does Sick Building Syndrome exist?

“Sick Building Syndrome” (SBS) is a term used to describe a situation in which occupants of a particular building have experienced acute health effects that seem to be correlated to time spent in the building, but a specific cause or illness can not be identified. SBS can be throughout the building or in a particular room or zone.

In contrast, “Building Related Illness” (BRI) is a term used when symptoms of an illness are identified and are directly attributed to airborne building contaminants.

Although specific causes are unknown, some contributing factors to Sick Building Syndrome include chemical contaminants from both indoor and outdoor sources, inadequate ventilation, and biological contaminants such as mold, pollen, bacteria, and viruses.

Some solutions to SBS include removal of bacterial contaminant source, increasing ventilation rates and air distribution, as well as air filtration systems to clean the air.

What is Negative Pressure?

Negative pressure is when a room inside the building is held at a lower pressure than the surrounding rooms. Or to put it another way, negative pressure occurs when more airflow is drawn out of a room then airflow pumped in. This ensures any air leaks in the room will flow from outside the room to the inside. This is most commonly used in hospital isolation rooms to prevent airborne viruses or bacteria from escaping the room into other rooms.

What is Positive Pressure?

Positive pressure is when a room inside the building is held at a higher pressure than the surrounding rooms. Or to put it another way, positive pressure occurs when more airflow is pumped into a room then airflow drawn out. This ensures any air leaks in the room will flow from inside the room to the outside. This is most commonly used in clean room applications to prevent airborne contaminants from outside the room leaking in.

How do I size an air cleaner properly?

Visit our sizing program, or call us at 1-888-883-3273 and we can help you over the phone.

What is source capture?

A product intended to draw in the pollutant directly at the source creating the contaminant (for example, using a small flexible arm to draw away the smoke from a soldering iron or arc welder).

What is an ambient cleaner?

What is an “in-duct” air cleaner?

Typically refers to a cleaning device with just a filter. The motor blower is already in the ductwork.

What is a self-contained air filtration system?

Typically refers to a system that has both a filter and a motor blower to move the air.

What does depth loading vs. face loading mean and what is the advantage to each?

Depth loading a filter refers to a filter of various density. Initially the looser matrix of fibers will catch only the large particles, allowing the smaller particles to pass. As the matrix of fibers becomes more tight than smaller particles will be caught. The advantage to a depth loading filter is the amount of dust holding capacity.

A face loading filter will capture all the particles on the media. These filters are designed to fill up fast with particles but their advantage is they can be cleaned easily. In many dust collectors with self cleaning or pulsing mechanisms they will get a blast of air from the clean side and the particles will fall down into a collection hopper.

What does delivered airflow mean?

Delivered airflow is the actual volume of air that the filtration system is moving.

What is free air?

The amount of air delivered from a fan or blower without any restrictions, i.e., air filter, housing, ductwork. Free air numbers are always higher than what the air cleaning device can actually deliver. Many companies will advertise their cleaner’s air flows from free air readings. When considering a filtration system, be sure to know whether the published airflow is the “delivered airflow” or the “free airflow”.

How do I select the right air filtration system?

Contact Air Quality Engineering at 1-888-883-3273. We can get information from you regarding your specific application and assist you with your selection, or you can analyze the factors for yourself. We pride ourselves on the level of service and expertise that we offer.

What is an ozone generator?

An air cleaner that is specifically designed to intentionally produce ozone gas are called ozone generators. Ozone is a toxic triatomic molecule consisting of three oxygen atoms. Two of the atoms make up the basic oxygen molecule while the third atom can detach from the other two and re-attach to molecules of other substances. Due to certain health risks, the National Institute of Occupational Safety and Health, the Occupational Safety and Health Administration, and the Food and Drug Administration have put in place public health standards to limit human exposure to ozone. For more information on ozone generators, visit the U.S. Environmental Protection Agency’s website to read their assessment on ozone generators sold as air cleaners.

How does an electrostatic precipitator work?

A high voltage power supply is used to generate an intense ionization field at the inlet side of the cleaning device. Airborne pollutants that pass through the ionization field become positively charged. The positively charged particles are then collected on the electrostatic collector cell fins where they become trapped and remain there until the cell is washed.

What is an ionizer?

An ionizer is a device that electronically disperses negatively or positively charged ions into the air using high voltages. The charged ions attach to molecules and particles in the air and give them a charge so they can attach to one another and settle out of the air.

What are HEPA, ULPA, SULPA and Ultimate ULPA?

HEPA (High-Efficiency Particulate Aerosol) – HEPA filter has a minimum particle collection efficiency of 99.97% for particles 0.3 microns in diameter.ULPA (Ultra Low Penetration Aerosol) – ULPA filter has an efficiency of 99.999% for particles in the most penetrating particle size at the specified media velocity. The most penetrating particle size is the particle diameter when penetration through the media is highest.SULPA (Super ULPA) – At an efficiency of 99.9999% these filters are based on the same standard as the ULPA filters.Ultimate ULPA – At an efficiency of 99.9999999% these filters are based on the same standard as the ULPA filters.

What is an ESF?

Extended Service Filter. These filters feature longer life than standard filters, due to a lot more surface area.

How does a media (paper) filter work?

Mechanical filters are made of fibers. Air is passed through a filtration media and the particles are trapped by:

Impingement – Large particles collide with a fiber while air passes around the fiber.

Interception – Small particles move in the air-stream but are attracted to the fiber with a stronger force than carries the particle in the air stream.

Diffusion – Very small particles too small to follow streamlines will follow irregular paths because they are being hit by gas particles. (This irregular path is called the Brownian Movement.) These particles collide with fibers and are retained.

Straining – a particle is too large to pass between the gaps in the fiber matrix. (This is like a tennis ball getting stuck in a chain-link fence.)

In most filters treating domestic air, all of these filtration effects are happening at once, giving an overall particle removal efficiency.

What is the difference between a media and electronic cleaner?

Electronic air cleaners have come to mean a wide variety of technology but most commonly refer to either electrostatic precipitators or ionizers. Electrostatic precipitators consist of a high voltage ionization section followed by a collector section which also uses a high voltage field to electrically trap the particulates which are later removed by washing the collector cell. Electronic cleaners may also be used to describe ionizers which simply emit charged particles out into the atmosphere which then attract and electrically bond to other airborne particles until they eventually become electrically bonded to a surface such as a wall, ceiling, floor or items within the area. Although uncommon, electronic filtration systems may also be used to describe ozone generators (uncommon), which are not recommended to be used as cleaners. (Source: https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-are-sold-air-cleaners)

Media filtration products generally use a disposable fabric type filter to capture particulates and achieve their efficiency. A HEPA filter is a common example of a media filter – although filters are available in a wide variety of media efficiencies, styles and materials.

Why not just open a window instead of using an air cleaner?

Unless you are fortunate enough to live in an area where the outside air is always between 72F and 78F you’ll waste the money spent heating or cooling the air in your home or business.

The air outside your home or business is not always as clean as you’d like especially in urban environments.

A properly installed air cleaner generates better airflow patterns for removing contaminants than just opening a window.

What is a MERV rating?

MERV is an industry standard rating, so it can be used to compare air filters made by different companies. Some manufacturers also have their own rating systems.

Comparison of the 52.2 (MERV) and 52.1 Rating Systems

ASHRAE 52.2

ASHRAE 52.1

MERV

3-10 microns

1 – 3 microns

0.3 – 1 microns

Arrestance

Dust Spot

Dust Spot

1

<20%

–

–

<65%

<20%

>10 microns

2

<20%

–

–

65-70%

<20%

3

<20%

–

–

70-75%

<20%

4

<20%

–

–

>75%

<20%

5

30-35%

–

–

80-85%

<20%

3.1-10 microns

6

35-50%

–

–

>90%

<20%

7

50-70%

–

–

>90%

20-25%

8

>70

–

–

>95%

25-30%

9

>85%

<50%

–

>95%

40-45%

1.0-3.0 microns

10

>85%

50-65%

–

>95%

50-55%

11

>85%

65-80%

–

>98%

60-65%

12

>90%

>80%

–

>98%

70-75%

13

>90%

>90%

<75%

>98%

80-90%

0.3-1.0 microns

14

>90%

>90%

75-85%

>98%

90-95%

15

>90%

>90%

85-95%

>98%

~95%

16

>95%

>95%

>95%

>98%

>95%

17

>99%

>99%

>99%

–

>99%

0.3-1.0 microns

18

>99%

>99%

>99%

–

>99%

19

>99%

>99%

>99%

–

>99%

20

>99%

>99%

>99%

–

>99%

Who is MERV and how does he rate?

MERV stands for Minimum Efficiency Reporting Value. The MERV rating evaluates the effectiveness of air filters.

What is the difference between ASHRAE 52.1 and 52.2?

Standard 52.1-1992: Consists of two tests, the atmospheric dust spot efficiency test and a dust arrestance test. The arrestance test quantifies filter efficiency by mass of particles removed or ‘arrestance’ and is generally only used to measure performance of prefilters or low efficiency filters – efficiencies measured by weight give little indication of their performance for the smallest, lightest particles (the most respirable and hazardous). The atmospheric dust spot efficiency test is based upon the amount of stain or discoloration that appears on a filter when subjected to specific test conditions and is not based on a specific particle size. The atmospheric dust spot efficiency is commonly shortened and referred to as ASHRAE efficiency.

Standard 52.2-1999: This test method actually counts the number of particles of varying sizes before and after a filter to determine its true efficiency to filter out particles of various size ranges by count. Standard 52.2 testing measures efficiency in 12 different size ranges between 0.3 micron particles up to 10 microns. This is the most recent standard in filter testing and provides a meaningful efficiency for a filter or air filtration system that can be compared between manufacturers.

What is ASHRAE?

American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. www.ashrae.org. ASHRAE establishes standards for testing and comparing the efficiency of filters or air cleaners.

How are air filters rated?

American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) has established standards, which primarily uses two different methods for describing filtration efficiency Test 52.2 and Test 52.1

What is an Air Cleaner or Air Purifier?

A device containing a filtering mechanism (filter), which is designed and used for collecting airborne impurities, such as, dusts, gases, smokes and fumes through the use of filters, electrostatic cells and/or absorbents. Typically an air cleaner has a motor blower.

What is an Air Filter?

Device used to separate out contaminants from air.

What is a Micron?

A millionth of a meter (μm). To put in perspective, the average human hair is 150 microns in diameter while dust is typically 5 to 10 microns in size.

Why is it important to clean the air?

“indoor air is often two-to-five times more polluted than outdoor air and can be up to 1,000 times as dirty. The EPA estimates that most Americans are exposed every day to indoor air contaminants than can lead to serious health problems for some people, including cancer, respiratory ailments, fatigue and headaches.”Congressional Quarterly

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